Abstract The reduction of substituted spiro-piperidinyl chromanone oximes with DIBAH reagents has been known to afford the corresponding substituted 4, 5-dihydro-3H-spiro [1, 5]- benzoxazepine-2, 4′-piperidine. The position and electronic effects of the substituents on the aryl moiety control the observed rearrangement. Spiro-benzoxazepine analogue 5j represents a key intermediate for the creation of a library of diverse potential bioactive ...